Effect of Cultivars, Harvesting Time and Level of Nitrogen Fertilizer on Nitrate and Nitrite Content, Yield in Romaine Lettuce

Maryam Boroujerdnia, Naser Alemzadeh Ansari and Farideh Sedighie Dehcordie

Asian Journal of Plant Sciences 6 ( 3 ): 550 - 553 , 2007